轴承钢马氏体-贝氏体复相组织的强韧性研究  

A Study of the Mechanical Properties of Martensite--Bainite Dual Phase Structure of Ball Bearing Steel

作　　者：徐佐仁[1] 黄兴家[1] 

机构地区：[1]上海交通大学材料科学及工程系

出　　处：《上海交通大学学报》1989年第4期8-19,共12页Journal of Shanghai Jiaotong University

摘　　要：本文研究了Gcr15轴承钢在M_s点上、下等温处理时的相变过程所获得的各种体积比的马氏体-贝氏体复相组织及其强度与韧性、并通过断口分析讨论了贝氏体体积率变化对断口形貌及断裂机制的影响。Gcr15轴承钢在稍低于M_s点的220℃等温4小时所得到的复相组织,弯曲强度比普通淬火、回火的提高1470MPa,冲击韧性增加1倍多,断裂韧性约递增70%。具有优异的强韧性配合。材料的力学性能潜力得到进一步发挥。An investigation was carried out about the various martensite-bainitedual phase structures and their strength and toughness at different volumefraction ratio when isothermally transformed at temperatures above or below.By way of fracture analysis, a discssion is presented in this paper on howfractography and fracture mechanism change with the variation of the volumefraction of bainite. The best combination of strength and toughness is achieved by the mar-tensite-bainife dual phase structure transformed isothermally at 220℃ for 4hrs. Its bending strength is about 1470 MPa and its impact toughness exceedstwo times over that of tempered martensite. Its fracfure tougness is enhancedby nearly 70%. The underdeveloped mechanical properties are better utilized.This is due to the thermally-formed prior martensite partitioning the under-cooled austenite grains, refining the effective grain size and lath dimensionof bainite successivelly transformed. The lower the transformation temper-aturesof bainite is, the finer the lath dimensions and the more dispersed thebainitic carbides would be obtained. All of these are advantageous to mech-anical properties of the dual phase structure.

关 键 词：轴承钢 马氏体 强韧性 贝氏体 

分 类 号：TG142.41[一般工业技术—材料科学与工程]